Association of high-sensitivity assayed troponin I with cardiovascular phenotypes in the general population: the population-based Gutenberg health study

Background

Aim of the study was to analyze the correlation of high-sensitivity assayed troponin I with cardiac and vascular structure and function in a large population-based cohort.

Methods

In a sample of 4,139 subjects (2,099 men, 2,040 women, age 35–74 years) from the population-based Gutenberg Health Study, troponin I was measured with a high-sensitivity assay that had a limit of detection of 1.9 pg/mL.

Results

In the study cohort, 3,405 subjects had detectable troponin I concentrations [82.3 % overall, 89.9 % men (N = 1,888), 74.4 % women (N = 1,517)]. All analyses were adjusted for age. The strongest correlate between detectable troponin I and measures of cardiac phenotypes was observed for left ventricular mass (p < 0.001) and left ventricular end-diastolic diameter (p < 0.001) for both, women and men. Left ventricular ejection fraction was inversely correlated with troponin I (p value <0.001 in men and 0.0013 in women), also measures of diastolic dysfunction as represented by Tei index and E/E′ correlated with detectable troponin I concentrations (p < 0.001 for both gender). With respect to vascular structure and function, troponin I correlated with mean intima-media thickness of the carotid artery (p < 0.001 in men and p = 0.013 in women) but showed only borderline correlation with measures of vascular function represented by flow-mediated dilation (p = 0.05 in women and p = 0.018 in men) and arterial stiffness.

Conclusions

Troponin I assessed by a high-sensitivity assay correlated with measures of left ventricular hypertrophy and systolic and diastolic function, whereas its correlation with vascular phenotypes was only of weak magnitude.     

Left atrial deformation imaging with ultrasound based two-dimensional speckle-tracking predicts the rate of recurrence of paroxysmal and persistent atrial fibrillation after successful ablation procedures

Predict AF. Objective: Since predictors of recurrence of atrial fibrillation (AF) after ablation procedures are poorly defined, this prospective study was conducted to assess the value of left atrial (LA) deformation imaging with two‐dimensional speckle‐tracking (2D‐ST) to predict AF recurrences after successful ablation procedures. Methods and results: One hundred and three consecutive patients (age 58.1 ± 16.6 years, 72.8% male) with AF (76 paroxysmal, 27 persistent) and 30 matched controls underwent transthoracic echocardiography and 2D‐ST‐LA‐deformation analysis with assessment of LA‐radial and LA‐longitudinal strain (Sr, Sl), and velocities derived from the apical 4‐ and 2‐chamber views (4CV, 2CV). AF recurrence was assessed during 6 months of follow‐up. For determination of AF‐related LA changes, AF patients were compared to controls and patients with AF recurrences after ablation procedures (n = 30, 29.1%) were compared with patients who maintained sinus rhythm (n = 73, 70.9%). Atrial deformation capabilities were significantly reduced (P < 0.0005) in patients with AF (4CVSl 17.8 ± 13.5%; 4CVSr 22.3 ± 14.9%; 4CV‐velocities 2.53 ± 0.97 seconds) when compared with controls (4CVSl 31.3 ± 12.4%; 4CVSr 30.3 ± 9.1%; 4CV‐velocities 3.48 ± 1.01 cm/s). Independent predictors for AF recurrence after ablation procedures were 2CV‐LA‐global‐strain (Sr, P = 0.03; Sl, P = 0.003), 4CV‐LA‐gobal‐strain (Sr, P = 0.03; Sl, P = 0.02), and regional LA‐septal wall‐Sl (P = 0.008). LA‐global‐strain parameters were superior to regional LA function analysis for the prediction of AF recurrences, with cutoff values (cov), hazard ratios (HR), positive and negative predictive values (PPV, NPV) were: 4CVSl cov, 10.79% (HR 27.8, P < 0.0005; PPV 78.8%, NPV 93.9%), 4CVSr cov, ?16.65% (HR 24.8, P < 0.0005; PPV 69.4%, NPV 96.6%), 2CVSl cov, 12.31% (HR 22.7, P < 0.0005; PPV 75.8%, NPV 95.3%), and 2CVSr cov, ?14.9% (HR 12.9, P < 0.0005; PPV 64.3%, NPV 93.2%). Conclusion: Compared with controls, AF itself seems to decrease LA deformation capabilities. The assessment of global LA strain with 2D‐ST identifies patients with high risk for AF recurrence after ablation procedures. This imaging technique may help to improve therapeutic guiding for patients with AF. (J Cardiovasc Electrophysiol, Vol. 23 p. 247‐255, March 2012.)     

Novel variants and clinical symptoms in four new ALG3‐CDG patients,review of the literature,and identification of AAGRP‐ALG3 as a novel ALG3 variant with alanine and glycine‐rich N‐terminus

ALG3‐CDG is one of the very rare types of congenital disorder of glycosylation (CDG) caused by variants in the ER‐mannosyltransferase ALG3. Here, we summarize the clinical, biochemical, and genetic data of four new ALG3‐CDG patients, who were identified by a type I pattern of serum transferrin and the accumulation of Man₅GlcNAc₂‐PP‐dolichol in LLO analysis. Additional clinical symptoms observed in our patients comprise sensorineural hearing loss, right‐descending aorta, obstructive cardiomyopathy, macroglossia, and muscular hypertonia. We add four new biochemically confirmed variants to the list of ALG3‐CDG inducing variants: c.350G>C (p.R117P), c.1263G>A (p.W421*), c.1037A>G (p.N346S), and the intron variant c.296+4A>G. Furthermore, in Patient 1 an additional open‐reading frame of 141 bp (AAGRP) in the coding region of ALG3 was identified. Additionally, we show that control cells synthesize, to a minor degree, a hybrid protein composed of the polypeptide AAGRP and ALG3 (AAGRP‐ALG3), while in Patient 1 expression of this hybrid protein is significantly increased due to the homozygous variant c.160_196del (g.165C>T). By reviewing the literature and combining our findings with previously published data, we further expand the knowledge of this rare glycosylation defect.